中国科学院重庆绿色智能技术研究院机构知识库

The effects of polarization on the common noble metal electrodes of YSZ oxygen sensor were studied through two electrochemical polarization modes, and the anodic and cathodic polarization model were proposed. The study indicates that with a controlled temperature of 500°C and ambient air condition, the Ag and Pd showed excellent electrochemical activity since the efficient transference of oxygen atoms by direct bulk diffusion and producing metal oxides; by the introduction of oxygen anion conductor YSZ, the effective reactive interfaces were greatly enlarged, so the activity of electrode was increased; the Ag-2%Pt electrode showed lower activity than the Ag electrode, but it present better anodic performance compared with the Pt electrode; while the Au electrode was polarized, the oxygen atoms were transferred only by adsorption, desorption and diffusion, that result in the low transferring efficiency, and especially the cathodic activity was very low.

采用两种极化方式研究了电化学极化对YSZ氧传感器中常用贵金属电极性能的影响,提出了电极阳极和阴极极化模型。研究表明,在500℃和空气条件下,Ag和Pd可通过体扩散和形成氧化物的方式实现高效的氧传质,电极性能较好;离子导体 YSZ的引入,可使Pt 电极有效反应界面得以扩展,电极性能得到增强;Ag-2%Pt 电极较 Ag 电极性能低,较 Pt电极阳极活性有所增强;Au电极极化时主要通过吸脱附和扩散进行氧转移,效率较低,尤其是阴极活性较低。